Improvement in balanced slide-valves



PATENT OEEICEo JOHN R. GROUT, OF DETROIT, MICHIGAN.

IMPROVEMENT IN BALANCED SLIDE-VALVES.

Specification forming part of Letters Patent No. 54,343 i dated May l, 1866.

To all whom it may concern:

Be it known that I, JOHN R. GROUT, of Detroit, in the county ot' Wayne and State of Michigan, have invented a new andim proved mode of preventing the pressure of steam upon the slide-valves of steam-engines and the wear of the valve; and I do' hereby declare that the following is a full, exact, and clear description of the same, reference being had to the accompanyin g drawings, making a part of this specification, in which- Figure l is a vertical section through the center of the valve and steam-chest in the direction of the motion of the valve. Fig. 2 is a vertical section through the center of the valve and steam-chest transverse of the direction of the valve motion. Fig. 3 is a face view of the valve. Fig. 41: is a face view of the stealnchest cover. Fig. 5 is a view of the nut securing the valve-rod to the valve. Fig. 6 is a face view of wire bar, side of steam-chest, and adjusting-screws. v

My invention consists in so constructing the valve and the cover of -the steam-chest as to counterbalance by compensating steam -surfaces the pressure of the steam upon the valve and the weight of the valve, and thereby save the power of the steam which this pressure and weight consume and the wear of the valve and f the surfaces against which the valve acts.

To 'viable others skilled in the art to make and use my invention, I will proceed to describe its construction and operation.

A is the ordinary steam-chest of steam-engines, into which the steam may enter at the end or the side in the usual way.

B is the steam-chest cover, and O is the valve. The valve occupies the usual area at its seat a,

and is fitted steam-tight in the outer area of its face b-with the steam-cover. It has open spaces through lit, c, in the direction of its motion, and also around it, d, which spaces admit of the free action of the steam in the 'steamchest. The valve is made of the same size at its seat a and at the cover of the steam-chest b, to the end of counterbalancing the pressure of the steam upon it, and a little Wider at the cover transversely of the direction of the valve motion than at its seat, to the further end of counterbalancing its Weight.

The valve being steam-tight with the steamchest cover, and of the same size at cover and at seat, and it being in position closing the steamports e when the steam is admitted, it is not then sensible to any pressure of the steam, for the pressure of the steam acting downward upon the valve is compensated for by its pressi ure against an equal surface actin`g upward on it, and is counterbalanced.

On movement of the valveso that the steam The steam escaping from the cylinder and y entering the exhaust-chamber gpresses upward against the valve. I compensate for this pressure by making a chamber, h, in the face b of the valve, which is of the same surfacearea as exhaust-chamber g, and exactly above it, and I connect chambers g and h by two free openings, t t, Fig. 2. The exhausting steam passing through these openings into chamber h, its pressure acts downward on the valve there at the same instant and with the same force that it acts upward against it in the exhaust-chamber g, and is counterbalanced.

At the moment the valve reaches the point of steam-exhaust, recess f connects with chamber h and the. steam in f escapes into h, Fig. l, meeting the exhausting-steam entering h through i z', Fig. 2. The steam of f and lb then escapes through t' i into chamber g, which is open to the exhaust-port. f and h receive steam from different sources and counterbalance the steam-pressure on different parts of the'valve, but in the exhausting of 'the steam they act in combination with z' i and g, and hence their perfect effectiveness, with the aid of the latter, in continuing the counterbalancing action.

I compensate for the weight of the valve by making its surface area larger at the steamchest cover than at its seat. I do this by giving the valve more breadth transversely of the the valve. The upward pressure ofthe steam then counterbalances its weight.

This manner of compensating for the pressure of steam in the slide-valves of steam-engines compensates also for the pressure of the atmospere against the steam at the exhaust-l ports, relieving the valve from any atmospheric action,'and it is equally applicable to free hi gh-pressure engines, high-pressures With constrained exhaust-as locomotive-'enginesand to low-pressure engines.

The valve hein g relieved from any pressure of the steain,and from its own Weight, there is still this essential condition It must Work steam-tight at its seat and at the cover, and must notbind in any part. Being itted, in the rst instance, in this manner, When steam is admitted to the steam-chest, the valve receiving and retaining the full heat of the steam, it will expand more than the sides of the steamchest, and bind or not move free. To compensate for or relieve it from this ett'eet I slightly incline the face of the valve transversely of the direction ot' its motion, giving to the face of the steam-chest cover the same inclination, as shown by the line j k, Fig. 2, and I place Within the steam-chest and along the heel of the valve a steel bar, l, held and operated by screwsm, tapped through the side ofthe steamchest, as shown, Figs. 2 and G. By this inclination of. the valve-face and the action of this Wire bar slightly setting the valve avvay from that side ot' the steam-chest by force ot' the adjusting-screws, any binding of the valve arising from its expansion from the heat of the steam is relieved, and the valve, once relieved under its full expansion by thus setting the Wire bar, Works free and steam-tight thereafter. WVhile the bar acts as a guide to the valve the force of the steam on the large surface area ot its opposite side keeps the valve steadily in place against the bar. This inclination of the face of the valve allows the valve to Work away from the adjusting Wire bar and its tight connection With the steamchest cover, and to become perfectly free in engines running with steam oft', as locomotiveengines running` down grade.

I make an oblong opening, n, through the valve to receive the valve-rod, which admits of the .necessary lateral movement ofthe valve, and attach the rod to the valve by T-nuts 0, Fig. 5, which lock by a shoulder on the valve, holding it rm and allowing of the lateral motion.

What I claim as my invention, and desire to secure by Letters Patent, is-

1. The recess or chamber h, formed in the vupper face ot the valve, substantially as and for the purpose set forth.

2. The counterbalancing-chamber 71J in the upper face of the valve, in combination with the openings i il from exhaust-chamber h, for the purpose substantially as herein described.

3. The recesses in the chest-cover and the chamber la in the upper face of the valve, in combination with openings 'ii and exhaustchamber g, operating substantially as herein set forth.

4. The Wire bar I, constructed and arranged to operate substantially as herein described.

Detroit, February 8, 1865.

. JOHN R. GROUTL.

Witnesses:

JULIUs S'roLL, EDWARD Y. SWIFT. 

